1. Field of the Invention
The present invention relates generally to apparatus for use in removing water pumps from deep wells for servicing thereof and more specifically to an improved hydraulic apparatus having a number of novel features designed to increase the convenience and decrease the difficulty associated with pulling an electric pump out of a deep well to service or replace the pump and reinstall it.
2. Prior Art
There are many areas in the United States where, unlike large cities which provide water from a central source to all its residents, each individual resident must provide his or her own source in the form of a water well. Typically, such water wells can be quite deep, depending upon the water table level in that area. In modern well water systems, the water is delivered to the surface through a long pipe usually made of polyvinyl chloride plastic by means of an electric pump and associated motor, both of which are positioned at the bottom of the well. Furthermore, the well is normally a very narrow shaft dug through the earth's surface to the depth required to reach the water table. The shaft is normally enclosed by a metal well casing to secure the shaft against collapse. The motorized pump is usually connected to an electrical source at the surface, thereby requiring the use of a long electrical cable which is normally affixed to the exterior surface of the pipe throughout the full length of the shaft.
Occasionally it becomes necessary to service the pump and motor or replace one or both such mechanisms and the length of the shaft, the weight of the pump motor and the pipe make it virtually impossible to manually pull the combination of pipe and pumps out of the well casing. Thus it becomes necessary to use a source of lifting power, typically provided by a hydraulic truck which provides a lifting force necessary to remove the pipe and the pump and then replace them and reinstall that combination after servicing is completed. Typically, the elongated plastic pipe that is attached to the pump at the bottom of the well casing and which brings the pumped water up to the surface, is provided in the form of a large plurality of pipe sections arranged in series and threadably interconnected one to the other in sequence. Typically, as the pipe and pump are withdrawn from the well casing, the threadable sections are disengaged from one another one at a time as the pipe is pulled to the surface and eventually the pump is pulled to the surface. As each pipe section is disengaged from the remaining pipe sections, the electrical cable connected to the exterior surface of the pipe must be disconnected so that eventually when the pump reaches the surface, one has a large plurality of pipe sections and a large length of electrical cable still connected to the pump to deal with.
Typical prior art relevant to the present invention includes other types of hydraulic systems which provide a power lifting capability for pulling the pipe and attached pump and motor to the surface of the well casing. However, the manner in which each pipe section is held in place while being unthreaded from the remaining sections and the manner in which the wire is handled as it is disconnected from each corresponding pipe section, leave much to be desired in terms of convenience and pipe and cable handling simplicity. Basically, service personnel required to pull the pipe and pump to service the pump are left to their own devices which can lead to damaged pipe sections, damaged pumps, a rat's nest of scrambled electrical cable and the potential for a costly or even tragic accident which can make the process of pulling a deep well pump and associated pipe a risky task at best.
There is therefore a continuing need for an improved hydraulic assembly for pulling a deep well pump and associated pipe and cable.